Ignition-testing device for internal-combustion engines



I June 14, 1927.

c. D. BOURCIER IGNITION TESTING DEVICE FOR INTERNAL COMBUSTION ENGINES I File d June 20. 1925 f. Iwm nw 65 W0 1 Patented June 14, 1927.

} UNITED STA CHARLES D. BOURCIER, GRAFTON, -MASSAGHUSETTS.

IGNITION-TESTING DEVICE-EOEINTERNAL-COMBUSTI01\T enemas.

Application filed June 2o, 1923. Serial No; 646,582.

My invention relates generally to a de- VICG'fOI usein connection with the ignition system of an internal. combustion engine and more particularly to a testing device for vehicle.

The object of my invention is to provide an. improvedtesting device of the above described character; whereby the spark plugs of different cylinders of the engine may be individually tested; at a point convenient for: the operator while the engi'neis running; 111E vorderr to: determine whether the several spark plugs ane properly receiving ignition current; andualso to determinewhether or,

not the spark plugs themselves are function;

in r ro erl. 1.: im roved device is so ar ranged tliatxeachucylinder' can be separately tested: in: full i view of the" operator without V interfering; with the normal operation of" tlIeen g'ine",1a-nd while the vehicle is; l motiom;

l he above and other advantageous fem tunes of my invention will' hereinafter more fully appeartreterence' being-had to the accompan ving -drawmgs; 1n rwhlchf Fig.1 1s a diagrammatic VIEW lllustratlng the application of my improved, testing de vicex to an internal combustion: engine.

Flip 2 1s; a: NIBWJIl 'fTOIliLBlBVHLlOII of my devices Fig. 3 is a transverse sectional view'alohg the line 3, 3,. ofiFig 2,;loo'king'in the direction of the arrows I p Fig: 4 is atperspecti've View showing the testing base and? finger removed f from the device I Ihilre "reference characters 1 refer to: like parts in"tl1e diff erent figures; 1

Referring first to" Fig. 1, the cylinden' blookrof an internal combustion: engineisdndicated at A,1 and: for thepurposeof illustratsioir :thei block: A is' shown: as comprising;

six cylinders provided with." spark plugs 1,

2,;3, 4,5 and G, although: it iszto be-under StObdl. that. my device: can be used'in connection with .anengine having any other desired rent is supplied to the plugs l to: 6-," inclusive,- in properwsequence for the firing :order' of the engine": As is custom'ary' inanost internal' combustiom: engines, the cylinderblock nected to the plug 1? by the wine 13,"the ten:

provided in the-board" B" and the opening 25" A is grounded, and thespark in each cyhn; (lcr is obtained by, the currentjumping to.

ground across the gap G between the spark? phrgrpoints, as clearlyshown. in: Fig; 31:"

Aportion of theinstrumentboard' B1 of an automobile or other vehicle is illustrated :isshown as being mounted onthe. board 13,"

although it'm-(ty aswell'be mounted atiotheii places'on the vehicles, as. maybe desired? A plurality of testing. wines-1 1' 3, 14:, '15, 16,91 and 1 8/, inclusive, lead fromrthe: sp arkplugs 1, 2, 3,14. 5' and 6;respe'ctivelyatona testing device which will now beide scribed with rel} enence to Figs. 2,3andr4'. i

My 'mproved device co-nsistsigeneral ly of T a :base' 19' composed of? suitablewinsulati'n material,. such as hard rubb'enor fibreyaind provided with a plurality loftcircumferem tially arranged openings 20, extending therethrough... The number of'openings 20 corre-vspend: to the: number of spark plugs,- and testing-terminals 1, 2, 3*,43: 5 and 6* are arranged in openings 20 'in" the same order! asthe-spark plugs, the terminal 1 being-con minal: 2? being connected tothe plii'g 2 by the: wire' 14,1and soon. The several termi nals'l to 6","inclusive, projectbeyond the rear face of the base 1 9 and the projecting- 'portionsnauereceived ino'penin'gs 21, pro- 9O rial, which "is secured to the base- 19i iv The I vidediin a block 22, also of insul'ati'ng mateseveral wires 13 to 18, inclusive ,'are -provided at their ends with plugs 2310i? well-' known type whiclrare received in recesses 24ipr0v1de'd: In the testingytermmals 1" to 6*,

inclusive, whereby the severalterminals may I be? conveniently connected to their respec tlVBEspark r p The b'look'22 isreoeivedi in Opening 25:

is surrounded byan annular plate 26 of'conductingmaterial. The plate 26 is grounded tothe frame' of the vehicle by anysuitable fmeans, such as thescrews 27 which secure-- number.of cylinders; The sparlt' plugs have connected theretoaigniti'on cables 7 8; 9, 10,

theplat'e26 tothe board B. The plate 261s engaged by: a ring 28 of conducting material which is turnable on a reduced cylindrical portion 29*of the base l9', a; flange 30 *pre :venting i lateral movement o f the ring 28.- The ring 28fcarries a testingpointer '31 Wlii'ch' xtend's beyond th flQhgGBWaHd is I bent over parallel to the face of the base 19;

, the openings 21 in the block 22.

The end of the pointer 31 is tapered and is of such length that when the ring 28 is turned on the base 19, the tip 32 0f the pointer 31 is adapted to pass successively directly in front of the terminals 1 to 6*, inclusive.

As best shown in Figs. 3 and 4, the openings 20 are countersunk, as indicated at and the several testing terminals 1 to 6, inclusive, terminate within the countersunk portions 33 slightly below the face of the base 19. hen the pointer 31 is positioned directly over a testing terminal, its tip 32 is substantially in engagement with the terminal.

The ring 28 is surrounded by a cylindrical casing 34, preferably composed of insulating material, which casing is in threaded engagement with the ring and carries a circular glass 35 which completely encloses the testing terminals and the movable pointer, so as to protect them and keep out the dust and dirt. The casing 3 1 being secured on to the ring 28, provides a member which may be readily taken hold of by the fingers for the purpose of turning the ring 28and the pointer 31.

Having thus described the various parts entering into my invention, the operation thereof is as follows. When the engine is operating properly, the pointer 31 is normally left in a neutral position intermediate any pair of adjacent testing terminals, such as 2 and 3*, so that the distance between the tip 32 and these points is so great as to preclude any possibility of a discharge. In order to insure against any premature functioning of my testing device when the engine is running properly, I have purposely located the terminals 1 to 6 inclusive, well Within the countersunk portions 33 to prevent a discharge between adjacent terminals,

and have furthermore disposed the connec- :ors between the terminals 1 to 6 inclusive,

and the wires 13 to 18, inclusive, well within When itis desired to test the ignition sys tem of the engine, in the event that a miss in the firing is noticeable, the operator has only to takehold of the casing 3 1 and turn the same slowly in either direction. Turning of the casing 3 1 causes the pointer 31 to move therewith in the direction of one of the testing terminals 1 to 6, inclusive. As the pointer 31 approaches a terminal, such as 3, a discharge will take place if ignition current is being properly supplied to the spark plug 3, and if such is the case, the pointer is then moved toward the next testingterminal a and the test repeated. If a discharge occurs between the pointer 31 and each of the testing terminals 1 to 6, the driver may then be assured that ignition current is being supplied to each of the spark plugs 1 to 6, and that the trouble does not lie in the distributor, or in any of the spark plug cables 7 to 12, inclusive. If, however, a discharge is not obtained at any of the terminals 1 to 6. inclusive, then the driver will immediately know that the trouble lies either in a faulty ignition cable or in the distributor itself. In other words. by moving thepointer 31 successively to the testing terminals 1 to 6", inclusive, the trouble is immediately localized.

Assuming that the operator has determined that ignition current is being supplied to all of the spark plugs 1 to 6, inclusive, and that the firing of the engine is still irregular, his next step is to determine which of the several cylinders is not firing properly. When making this test the pointer 31 is moved very slowly toward the terminal being tested, and when the discharge occurs, the driver carefully notices whether the firing of the engine is substantially the same as before, or whether there appears to be another cylinder missing. If the discharge, at

any particular terminal, results in increasing the misfiring, then the driver may conclude that the cylinder being tested is firing properly, inasmuch as the discharge to the pointer 31 shortcircuits the plug in question, and causes that particular cylinder to also miss. If, however, the discharge from a particular testing terminal occurs without increasing the misfiring, then the operator may conclude that while the corresponding spark plug is properly receiving ignition current, the plug itself may be faulty. The suspected plug may then be removed and inspected, for either an. accumulation of carbon or oil on its points, or for improper spacing If upon replacing of its discharge points. this plug it is found that the trouble has not been remedied, then the operator must look elsewhere for the cause.

It also happens sometimes that'the ignition current supplied to a particular spark plug is of such low potential as to reduce the intensity of the spark produced by the plug, in which case the cylinder will fire irregularly, depending upon the load upon the engine. When such is the case, my improved testing device is particularly well adapted to locate the weak cylinder.

When making a test for the intensity of the spark of any particular cylinder, the pointer 31 is moved very slowly toward the terminal in question and the position of the pointer when a discharge occursis closely noted. If the ignition current is of low intensity the discharge will not occur until the tip 32 is very close to the testing terminal, and this fact will serve to indicate that the proper ignition current is not being supplied to the spark plug in question, due to either a faulty ignition cable or distributor.

From the foregoing, it is apparent that by my invention I have provided an extremely effective device for testing the ignition system of an internal combustion engine.

I claim:

1. In an ignition testing device, a base composed oflnsulating material, a plurality of testing terminals mounted in said base, a metallic ring rotatably mounted on said base, a testingpointer connected to said ring, and a casing composed of insulating material attached to and entirely surrounding said ring, whereby to turn said ring and said pointer by manipulation ofsaid casing.

2. In an ignition testing device, a base composed of insulating material, aplu rality of testing terminals mounted in said'base, a metallic ring rotatably mounted on said base, a testing pointer connected to said ring, an annular casing composed oiinsulating material attached to and entirely surrounding said ring, anda glass front received by said annular casing, whereby said ring and pointer may be turned by manipulation of said casing Without the operator under any condition receiving any shock.

Dated this 8th day of June, 1923.

CHARLES D. BOURCIER. 

